Can type containers made of specific light metal alloys are commonly used for holding liquids such as beverages. Such containers are produced through a series of complex and high energy-consuming processes such as high-temperature melting, molding, forming, profiling, cleaning, coating and double seaming of a can lid, which requires specialized multi-head equipment.
The production of such a can requires a number of separate and costly technological processes. Such a can is opened by a lever system, by moving a pre-incised weakened part of the top lid and pressing it inside the can.
Closures of containers for liquids such as beverages may be made of plastics. Generally, they comprise a cylindrical or similarly shaped container and a separate closure or lid of relatively elastic material.
Expandable closures of certain types may be placed loosely in a container opening and are then expanded until they contact the inner surface of the container opening walls. There are also elastically deformable closures for a cylindrical container in which a sealing flange extends conically, and its largest outer diameter is greater than the inner diameter of the container walls in the area of a container opening.
Existing closure structures are often not sufficiently resistant to pressure increase caused, for example, by heating the container, or for keeping the constant pressure of a carbonated beverage. Pressure increase may also result from dynamic liquid pressure caused by sudden movement of the container which exert increased pressure on its closure.
The drawbacks of metallic (aluminium) cans are excessive energy consumption in production, large amounts of generated toxic waste, the necessity of interoperational transport and complex recycling.
Beverages in aluminium cans often lose their taste, no 3D ads can be placed on the cans, it is impossible to close a can multiple times, and the drinking opening in the can is not ergonomic.
An alternative to metallic cans are containers made of thermoplastic materials sometimes resembling the metal cans, made in one single technological operation. Such cans are easy to recycle and are much more economic than the aluminium ones. However, such containers do not provide repeated quick closing and opening of such containers nor are such containers free from the drawbacks of the existing solutions.
Container closures may benefit from improvement.